Abrasive compound



Patented Sept. 1931 UNITED STATES PATENT OFFICE ROBERT S. LEATHER, OF WATERBURY, CONNECTICUT, ASSIGNOR TO THE LEA MANU- FACTURING COMPANY, OF WATERBURY, CONNECTICUT, A CORPORATION OI CON- NECTICU T ABRASIVE COMPOUND 1T0 Drawing.

This invention relates to abrasive preparations, and more particularly to improvements in solid com ositions adapted to be transferred by friction to a revolving buf- 5 fing Wheel for polishing or finishing the surface of a metal or other material.

One object of the present invention is to provide a preparation ofthe above nature which will produce a flexible abrasive coating which will adhere tenaciously to the revolving wheel.

A further object is to provide an abrasive composition of the above nature which may be cheaply manufactured, which will be easy and safe to apply, which will produce a lasting finish, and which when properly encased will not deteriorate in storage.

A further object is to provide a nongreasy abrasive metal finishing composition, the use of which will eliminate the final washing and drying operations.

A further object is to provide an abras ve composition of the above nature which when in use will effect a great reduction in the amount of spoilage and rejections of the metal articles being finished, due to the clunination of staining or scratching occurring 1n the final washing and drying operations.

Abraded surfaces on metal articles have 8 generally been produced in the past by the use of compositions containing powdered abrasive mixed with a binder of wax or grease. It is a general property of such binders that they permit an undesirable lubricity or slip of the abrasive particles, which prevents the polishing composltion from developing the full cutting abllity of the abrasive.

A further objection to the use of such nondrying greasy binders is that a certain amount of the composition is deposited upon the metal being polished. This not only covers up the surface of the metal and adds to the operators difficulty in observing the progress'of the work, but also necessitates an elaborate series of cleansing and drying .operations before the work can be lacquered, or covered with some other protective coating.

The above objections have been overcome to some extent in the past by the use of an Application filed December 1, 1980. Serial No. 499,411.

abrasive com osition having a binder conslsting essentially of glue and water. When this composition was applied to the bufiing wheel, it would dry out hard and hold the abrasive particles firmly. As a result, the full cutting power of the abrasive was developed, and at the same time, since none of the composition was transferred to the ma terial being finished, the surface thereof remained clean and the finish being produced would be visible to the o erator at all times. Moreover, when the finis in operation was completed, the clean dry nished surface could be immediately lacquered or subjected to any other subsequent operation.

In practice, however, an abrasive composition having a binder consisting merely of glue and water was subject to the gross deect that when heated, as in warm weather,

it softened to such an extent as to be practically unusable. In other words, a bar of such abrasive composition which would serve with entire satisfaction in cold weather, in warm weather would break up into large pieces when applied to a bufiing wheel and often would become smeared in thick, uneven, loosely-adherent layers over the wheel, instead of forming the thin, uniform, firmly adherent film desired.

By means of the present invention, the above and other disadvantages have been avoided. This result has been achieved by adding to the basic mixture of glue, water andabrasive, which may or may not contain a preservative, other ingredients which control the softening point and working qualities of the composition.

One means of accomplishing the same result was disclosed in my prior Patent No. 1,748,778, issued February 25, 1930. The composition covered therein contains a small percentage of formaldehyde chemically combined with the glue for the purpose of elevating the softening point of the composition.

The present invention lies in the discovery that this same elevating of the softening point of the glue-water-abrasive composition may be secured by ingredients which are not in chemical combination with the glue. It has been found that the addition to the basic glue, water and abrasive mixture of considerable proportions of various water-soluble compounds which do not combine chemically with the glue, but which are present merely in physical admixture, will also produce abrasive compositions in which the softening temperature is elevated.

Among the materials which may be so employed, ethylene glycol and diethylene glycol have been found satisfactory, the latter being preferred.

Two specific examples of how the invention may be embodied will now be described. According to the first example, 2? pounds of hide glue are first soaked in 54 pounds of cold water from one to two hours, and the glue is then melted by gentle heating. The mixture will then be transferred to a mixing vessel and pounds of diethylene glycol together with 300 pounds of SOO-mesh powdered silica added in succession. After the mixture has been stirred to thoroughly incorporate the abrasive it will be cast into suitable molds or containers in bar shape. After allowing the bars to cool and set, the containers of solid moist composition may be shipped to the trade. The mixture after pouring will then have the following proportions: glue 6.3%, water 12.7%, diethylene glycol 10.6%, and powdered silica 70.4%.

The glue acts as a binder for the other ingredients and causes the abrasive to adhere to the wheel. The water acts as a solvent and a softening agent. The diethylene glycol forms a physical mixture with the other ingredients and raises the softening temperature of the mass, so that the composition may be eificiently used in warm weather. It also serves as a preservative. If desired, an additional preservative may be added to the above composition to enhance the keeping qualities thereof.

According to the second example, 27 pounds of hide glue are first soaked in 45 pounds of cold water from one to two hours, and the glue is then melted by gentle heating. The mixture is then transferred to a mixing vessel and 54 pounds of ethylene glycol together with 300 pounds of 300-mesh powdered silica added in succession. The mixture is then thoroughly stirred, cast into molds and cooled as in the first example. The mixture after pouring will then have the following proportions: glue 6.3%, water 10.6%, ethylene glycol 12.7%, and powdered silica 70.4%. The ethylene glycol acts in the same way as the diethylene glycol of the first example.

As a further disclosure of modifying the properties of a glue-water-abrasive composition, it has been found that if to either of the two examples just described a small proportion of a lubricant, such as oil, grease, fat, or wax be added, in an amount not sufficient to effect the non-greasy character of the composition, there will result a slight reduction in the cutting power of the abrasive. This effect is obtained without any noticeable impairment of the drying power of the compound on the buffing wheel, or of its'clean working characteristics. As an example of such a lubricant, 4 pounds of beef tallow may be added to the compositions in either example and mixed therewith as a final step before pouring into bar form.

In use, the end of the bar of composition will be pressed against a revolving bufing wheel of felt, muslin, leather, or other flexible or semi-flexible material. The bar is held against the revolving wheel until a thin layer of the compound has been deposited thereon. The wheel with its thin flexible coating is then ready for the polishing or finishing o oration in which the article will be he d against the revolving wheel until the de sired abrading action has been secured. The

article may then be lacquered or coated in the usual way without the necessity of washing and drying. The wheel may be maintained in proper working condition by the application of small quantities of the compound as required.

While there has been disclosed in this specification several examples of how the invention may be embodied, it will be understood that the invention is not to be limited to these examples, but may be modified and embodied in various other ways without departing from its spirit. In short, the invention includes all the modifications and embodiments 1- coming within the scope of the following claims.

Having thus fully described the invention, what is claimed as new and for which it is desired to secure Letters Patent, is:

1. A solid abrasive preparation comprising a mixture of glue, water, abrasive, and diethylene glycol, said preparation being readily transferable to a revolving buffing wheel by friction.

2. A solid abrasive preparation comprising a mixture of about 6 percent glue, 13 percent water, 11 percent diethylene glycol, and percent powdered abrasive.

3. A solid abrasive preparation comprising a mixture of glue, water, abrasive, and an agent which is physically associated with said glue for raising the softening temperature of the mixture, said preparation being readily transferable to a buffing or polishing implement by rubbing.

4. A solid abrasive preparation comprising a mixture of glue, water, abrasive, and ethylene glycol, said preparation being readi 1y transferable to a revolving bulfing Wheel by friction.

5. A solid abrasive preparation comprisin a mixture of about 6 percent glue, 13 percent water, 11 percent diethylene glycol, 69 percent abrasive and 1 percent beef tallow.

6. A solid abrasive preparation comprising a mixture of glue, Water, diethylene glycol, abrasive, and grease.

7. A solid abrasive preparation comprising a mixture of glue, Water, diethylene glycol, abrasive, and a lubricant.

In testimony whereof, I have aifixed my signature.

ROBERT LEATHER. 

